Computer simulation has become an important tool in modeling systems in the last ten years due to
parallel improvement in computer technologies. Companies tend to computer based system modeling and
simulation not to lose any extra income or time to their competitors but to make future investments while they
both have the same labor force, resources and technology. This study is an implementation of a machine spare
parts manufacturer factory located in city of Turkey. The purpose of the study depends on increasing the
utilization rates and optimizing the manufacture process to decrease prouction costs via identifying the
bottlenecks in manufacture system. Therefore, ProModel simulation software was used to model the production
line of the factory. Production line consists of nineteen work stations and was modeled for the most
manufactured two products. The manufacture in the factory is divided into two weeks of batch production time
and simulation model was demonstrated and replicated for ten times to get results. Thus, statistics including
existing capacity usages of work stations in the whole production line were found to identify the bottlenecks
of the critical work stations and machines. With the use of the simulation model, creating scenarios while
making changes of the system parameters, taking the cycle times of the work stations, total production quantity,
batch sizes and the shifts of the factory in hand helped to make suggestions.